The Evolution of Worlds

by Percival Lowell

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CONTENTS

CHAPTER		PAGE
I.	Birth of a Solar System	[ 1]
II.	Evidence of the Initial Catastrophe in Our Own Case	[31]
III.	The Inner Planets	[58]
IV.	The Outer Planets	[94]
V.	Formation of Planets	[127]
VI.	A Planet’s History—Self-sustained Stage	[155]
VII.	A Planet’s History—Sun-sustained Stage	[182]
VIII.	Death of a World	[213]
NOTES
1.	Meteor Orbits	[241]
2.	Densities of the Planets	[243]
3.	Variation in Spectroscopic Shift	[243]
4.	On the Planets’ Orbital Tilts	[244]
5.	Planets and their Satellite Systems	[245]
6.	On the Induced Circularity of Orbits through Collision	[250]
7.	Capture of Satellites	[251]
	Index	[253]

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LIST OF ILLUSTRATIONS

PLATES
I.	Saturn	[Frontispiece] OPPOSITE PAGE
II.	The Moving Nebula surrounding Nova Persei, 1901-1902	[14]
III.	Representative Stellar Spectra	[24]
IV.	Spectra of the Major Planets	[52]
V.	Venus, 1896-1897	[82]
VI.	Asteroids: Major Axes of Orbits	[98]
VII.	Saturn—A Drawing showing Agglomerations	[108]
VIII.	Spectrogram of Jupiter, Moon Comparison	[152]
IX.	Spectrogram showing Water-vapor in Atmosphere of Mars	[160]
X.	Tree Fern	[176]
XI.	Ten Views of Mercury, showing Effect of Libration	[222]
XII.	Spectrogram of Saturn	[232]
CUTS APPEARING IN TEXT
PAGE
	Algol and its Dark Companion	[ 4]
	Nova Persei	[11]
	Spectrum of Nova Persei	[12]
	The Moving Nebula surrounding Nova Persei, 1901	[13]
	Great Nebula in Orion	[17]
	Great Nebula in Andromeda	[18]
	Nebula M. 100 Comæ	[19]
	Nebula ♅ I. 226 Ursæ Majoris	[20]
	Nebula ♅ V. 24 Comæ. Showing Globular Structure	[21]
	Nebula M. 101 Ursæ Majoris	[23]
	The Radiant of a Meteoric Shower	[37]
	Diagram explaining Proportionate Visibility of Meteors	[38]
	The Mart Iron	[41]
	Section of Meteorite showing Widmannstättian Lines	[42]
	Meteorite, Toluca	[43]
	Nebula ♅ V. 14 Cygni	[45]
	Nebula N.G.C. 1499 Persei	[46]
	Nebula N.G.C. 6960 in Cygnus	[47]
	Nebula M. 51 Canum Venaticorum	[48]
	Orbits of the Inner Planets	[59]
	Sulla Rotazione di Mercurio.—Di G. V. Schiaparelli	[64]
	Map of Mercury. Lowell	[69]
	Venus. October, 1896-March, 1897	[78]
	Venus. April 12, 1909.	[79]
	Diagram: Convection Currents in Atmosphere of Venus	[81]
	Diagram: Shift in Central Barometric Depression	[81]
	Spectrogram of Venus, showing its Long Day	[87]
	Spectrogram of Jupiter, giving the Length of its Day
	by the Tilt of its Spectral Lines	[89]
	Orbits of the Outer Planets	[95]
	Drawing of Jupiter showing its Ellipticity	[103]
	Two Drawings of Jupiter and its Wisps	[105]
	Photograph of Jupiter, 1909	[107]
	Diagram of Saturn’s Rings	[113]
	The Tores of Saturn	[114]
	Chart showing increasing Tilts of the Major Planets	[131]
	Orbital Tilts and Eccentricities of Satellites	[133]
	Masses of Planets and Satellites	[136]
	Two Drawings of Jupiter and its “Great Red Spot”	[164]
	Sun Spots	[165]
	Photograph of a Sun Spot	[166]
	The Volcano Colima, Mexico, March 24, 1903	[169]
	Jukes Butte, a Denuded Laccolith, as seen from the Northwest	[170]
	Ideal Section of a Laccolith	[170]
	Earth as seen from above.—Photographed at an Altitude of 5500 Feet	[183]
	Tracks of Sauropus Primævus	[188]
	Adventures of a Heat Ray	[193]
	Polar Caps of Mars at their Maxima and Minima	[198]
	Glacial Map of Eurasia	[200]
	Map showing the Glaciated Area of North America	[201]
	Photograph of the Moon	[205]
	Petrified Bridge, Third Petrified Forest, near Adamana, Arizona	[210]
	Three Views of Venus, showing Agreement at Different Distances	[220]
	Diagram of Libration in Longitude due to Rotation	[222]
	Moon,—Full and Half	[225]
	Diagram illustrating Molecular Motion in a Gas	[227]
	Distribution of Molecular Velocities in a Gas	[229]

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